Nelson worked with Sesame Street since 1970. There he played, among others, the figures Count von Count ( Count by Count ) beanpole ( Herry Monster), Sherlock Humbug (Sherlock Hemlock ) and the Grand balderdash ( The Amazing Mumford ). Together with Richard Hunt, and after his death in 1992 with David Rudman also played Nelson the Two -Headed Monster ( The Two Headed Monster).
The Muppet Show Nelson was primarily responsible for the musical roles. He played Kermit 's nephew Robin, Floyd Pepper, Camilla the chicken, as well as a high number of side characters. According to Richard Hunt's death, he also took on the role of Statler, he had already played in the pilot episode of the Muppet Show.
He played in the series Fraggle Rock Gobo Fraggle, the main character and Pa Gorg (only face and voice ) and Marjorie, the omniscient dump ( Marjory the Trash Heap ).
In 2004, Nelson moved for health reasons from the productions with characters from the Muppet Show back. But on Sesame Street, he was still with.
Nelson had a daughter, Christine, who suffered from cystic fibrosis. She had guest appearances on Sesame Street and the Muppets. In 1982, she succumbed to her illness.